Effect of Channel Estimation Errors on Arbitrary Transmit Antenna Selection for Cognitive MISO Systems

This letter analyzes the effect of channel estimation errors on the performance of cognitive multiple input and single output (MISO) systems with arbitrary transmit antenna selection. In particular, the channel estimation errors are caused by the partial channel information between the cognitive transmitter and the primary receiver. Utilizing the derived probability density function (PDF) of the received signal-to-noise ratio (SNR), the effective capacity of the considered systems is numerically evaluated, and a new closed-form expression for the case of perfect channel estimation is also derived. Simulation results show that the system performance is not sensitive to the channel estimation error, especially for strict delay quality of service (QoS) requirement of the cognitive user (CU).